Inkjet process for three-dimensional relief on tiles

ABSTRACT

A technique is described for the application of three-dimensional (3D) relief to a substrate such as a ceramic tile using digital inkjet technology. In an example embodiment, the introduced technique includes application of binder ink to a portion of the surface of a substrate using a digital inkjet process. This binder ink forms a barrier layer which protects the portion of the surface of the substrate. Next, a brushing process is applied to remove unprotected portions of the substrate, thereby forming the 3D relief in the substrate.

TECHNICAL FIELD

The present disclosure generally relates to processing techniques forforming textured relief in substrates such as ceramic tiles.

BACKGROUND

Tiles have a wide range of applications as building materials (e.g., forflooring) or as decorative objects. Various processes have beendeveloped to apply three-dimensional (3D) relief to tiles, for example,to improve functionality and/or add ornamentation. Existing approachesfor adding 3D relief to a tile include digital processes such as:additive processes whereby ceramic material is applied to the surface ofa tile, subtractive-like processes whereby a ceramic fluxing material isapplied to the glazed surface of a tile, and wax-resist processeswhereby a wax-like material is applied to the surface of a tile prior toglazing, as well as analog stamping processes whereby tile body powdersare pressed in a mold.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a flowchart illustrating a first example process forapplying a three-dimensional (3D) relief to a substrate using digitalinkjet technology;

FIGS. 2A-2C show a sequence of illustrative diagrams depictingprocessing of a first substrate according to the process of FIG. 1;

FIG. 3 shows a flowchart illustrating an example process that can beapplied to the substrate after the 3D relief has been formed;

FIGS. 4A-4C show a sequence of illustrative diagrams depictingprocessing of the first substrate according to the process of FIG. 3;

FIG. 5 shows a flowchart illustrating a second example process forapplying a 3D relief to a substrate using digital inkjet technology;

FIGS. 6A-6D show a sequence of illustrative diagrams depictingprocessing of a second substrate according to the process of FIG. 5;

FIGS. 7A-7C show a sequence of illustrative diagrams depictingprocessing of the second substrate according to the process of FIG. 3;

FIG. 8 is a diagram of an example automated production system that canbe configured to implement the introduced technique for applying 3Drelief to a substrate using digital inkjet technology; and

FIG. 9 is a block diagram of an example computing system as may be usedto implement certain features of some of the embodiments.

DETAILED DESCRIPTION Overview

Existing approaches for adding 3D relief to tiles have severaldrawbacks. For example, current digital processes (additive,subtractive, etc.) result in subtle, poorly defined relief effects dueto technological limitations. Further, existing digital processesinvolving subtractive methods sinking ink) typically involve the use ofheavy metals that are both toxic and significantly more expensive togenerate. Existing analog stamping processes can result in morewell-pronounced 3D relief patterns as compared to existing digitalprocesses. However, existing analog stamping processes allow for limitedvariation in relief patterns since every stamped tile will have the samerelief pattern until the stamping mold is changed. Generating newstamping models is costly and changing between stamping molds duringprocessing is both time and labor intensive.

Introduced herein is technique for applying 3D relief to substrates suchas tiles using a digital inkjet technology that addresses theabove-mentioned problems with existing approaches. In an exampleembodiment, the introduced technique includes applying binder ink to aportion of the surface of a substrate (e.g., a tile) using a digitalinkjet process. This binder ink forms a barrier layer that protects theportion of the surface of the substrate. Next, a brushing process isapplied to remove unprotected portions of the substrate, thereby formingthe 3D relief in the substrate.

The incorporation of inkjet technology in the introduced techniqueeliminates the need for expensive stamping molds while still maintainingthe durability of the surface of the substrate unlike existing digitalprocesses. For production efficiency, the introduced technique avoidsthe added time and labor needed to stop production to change reliefdesigns, reducing production costs and opens more design variability,for example, to mimic the look of “natural” materials. Further, theintroduced technique allows for the matching of relief patterns todigitally printed color designs later in the production process, therebyimproving design quality and enabling designers to diversify theirproduct offerings.

Terminology

Substrate: A “substrate” refers to any material upon which the disclosedtechnique for forming a 3D relief can be applied. In exampleembodiments, the substrate includes an absorbent layer of material uponwhich ink can be applied using an inkjet process and that can beremoved, for example, using a physical process such as brushing.Examples of substrates include hydraulically pressed ceramic green tile(single or double charged), glazed surface, or any other preparationwith similar characteristics. The substrate includes at least one (e.g.,a top surface) surface upon which the disclosed technique for reliefformation is applied. In some embodiments, the surface of the substrateis flat or at least substantially flat (i.e., little change in elevation(e.g., on the order of ±1 millimeter) relative to the length and/orwidth of the surface of the substrate) although the surface need not beflat in all embodiments.

Relief: Relief generally refers to a difference in elevation on asurface. As used herein, the terms “relief” or “3D relief” may refer tothe difference in elevation of the surface of the substrate resultingfrom the disclosed technique whereby material is removed from certainregions of the surface of the substrate. The pattern formed in thesurface of the substrate by the removal of material from certain regionsof the substrate is referred to herein as a “relief pattern.” As will bedescribed in more detail, the relief pattern can be defined based on adigital image. The relief formed in the substrate may exhibit variouscharacteristics such as depth and gradient. The depth of the relief maybe defined as a vertical distance relative to the original surface ofthe substrate. For example, the disclosed technique may involve removingmaterial up to a particular depth relative to the original surface ofthe substrate. The relief may also exhibit a gradient based on a ratiobetween a horizontal distance and a difference in elevation between twopoints. The gradient may exhibit a constant slope or a slope that variesover the horizontal distance between the two points.

Inkjet Printing: Inkjet printing generally refers to the process ofrecreating a digital image by propelling droplets of ink fluid onto asubstrate. Methods of inkjet printing include continuous inkjet (CIJ),thermal drop-on-demand (DOD) and piezoelectric DOD.

Binder Ink Fluid: Binder ink fluid or simply “binder ink” refers to anyfluid that can function to protect material of the substrate (e.g.,substrate powders) when applied. In some embodiments, the binder ink isa fluid that can be applied to the substrate using an inkjet printing toform a protective layer on the substrate. In the context of ceramic tilesubstrate, the binder ink is used to strengthen and protect the ceramicpowders in regions of the surface of the tile where it is applied. Thebinder ink fluid may comprise a resin/polymer aqueous-based orsolvent-based solution with properties suitable for use by an inkjetprinter. Depending on the specific implementation, the binder ink fluidmay include or be used in combination with other materials such ascurable materials (e.g., ultraviolet (UV), thermal, two-part, etc.), lowmelting point waxes, polymers, dispersed particles, or silanes. Thebinder ink fluid can be substantially transparent or may include a dyeor some other pigment to allow the placement of binder ink fluid on thesubstrate to be observed after application. In a ceramic process, anydye or pigment in the binder ink fluid may be organic-based to allow forremoval through incineration during the kiln firing process.

Solvent Ink Fluid: Solvent ink fluid or simply “solvent ink” can beapplied, for example using an inkjet process, on top of the protectivelayer formed by the binder ink, to produce gradient 3D reliefformations. When applied, the solvent ink forces the binder ink intosubstrate. The solvent ink fluid may comprise any type of solutioncapable of temporarily dissolving the resin (or other material) used forthe binder ink. Solvent ink fluids for aqueous and polar-solvent binderinks may comprise, for example, blends of any one or more of thefollowing example solvents: water, ethylene glycol, glycerin, ethyleneglycol ethyl ether, diethylene glycol ethyl ether, propylene glycol,dipropylene glycol, dipropylene glycol methyl ether, tripropyleneglycol, propylene glycol methyl ether, n-methyl-2-pyrrolidone, methanol,ethanol, isopropanol, n-propanol, butanols, ethyl lactate, acetone andother polar solvents. Solvent ink fluids for mid- to non-polar binderinks may comprise, for example, blends of any one or more of thefollowing solvents: aliphatic hydrocarbon distillates, ethyl acetate,propylene glycol butyl ether, dipropylene glycol methyl ether,dipropylene glycol butyl ether, tripropylene glycol methyl ether,ethylene glycol butyl ether, diethylene glycol butyl ether, methyl ethylketone, toluene, xylenes, tetrahydrofuran, methyl amyl ketone,cyclohexanone, and other non-polar solvents.

Brushing: After the binder ink sets, thereby forming a protective layerover the printed regions of the surface of the substrate, a brushingprocess is applied to physically remove material from the unprinted(i.e., unprotected) regions of the surface of the substrate. Thisprocess of removing material from certain regions of the surface of thesubstrate forms the 3D relief.

Glazing: A glaze may be applied as a post-process after forming the 3Drelief according to the disclosed technique. Application of a glaze istypically used in ceramics for decoration (e.g., to add gloss, texture,or color), to seal porous surface, and/or to add an additional layer ofprotection against wear. The glaze may comprise any material suitablefor the underlying substrate and may be applied using known glazingprocesses such as spray, waterfall, or digital inkjet.

Color Printing: Color printing may be applied as a post-process afterforming the 3D relief and/or applying a glaze to add decorative color.Color printing can be applied, for example, using digital inkjetprinting (as described above) or by using analog techniques such asgravure, screen printing, etc.

Firing: Firing, in the context of ceramic processing, generally refersto the process of applying heat to the material (e.g., clay and anyadded glaze) of a “green” substrate to form a final ceramic product. Atypical industrial ceramic tile process involves firing forapproximately 1-2 hours at a temperature between 1030° C. and 1250° C.

Example Processes for Applying 3D Relief to a Substrate Using DigitalInkjet Technology

FIG. 1 is a flowchart illustrating a first example process 100 forapplying 3D relief to a substrate using digital inkjet technology.Certain steps of the example process 100 are described with reference toFIGS. 2A-2C which show a sequence of illustrative diagrams depictingprocessing of a substrate according to the introduced technique. Certainsteps of the example process 100 depicted in FIG. 1 may be performed byone or more components of the automated production system 800 depictedin FIG. 8 and/or the example computing system 900 depicted in FIG. 9.The process 100 described with respect to FIG. 1 is an example providedfor illustrative purposes and is not to be construed as limiting. Otherprocesses may include more or fewer steps than depicted while remainingwithin the scope of the present disclosure. Further, the steps depictedin example process 100 may be performed in a different order than isshown.

Example process 100 begins at step 102 with receipt of an input whichdefines the relief pattern which will be applied to a substrate such asa ceramic tile. The input received at step 102 may include, for example,a digital image of a design upon which the relief pattern will be based.The digital image may comprise any type of data that can be processed bya computer processing system (e.g., processing system 900) to define arelief pattern to be applied to a substrate using the introducedtechnique. In some embodiments, the digital image may be a monochromeimage of a design defining a certain area corresponding to the reliefpattern to be printed. In some embodiments, the digital image may be apolychrome image which defines both the relief pattern to be applied aswell as coloring (e.g., through color inkjet printing) as a post-processafter applying the relief.

In some embodiments, the input received at step 102 may includeparameters associated with the processes to be applied to the substrate.For example, such parameters may include a type of substrate (e.g.,material type, dimensions, etc.), dimensions of the relief to apply(e.g., depth, gradient, etc.), selections of post-processes to apply(e.g., glazing, color printing, firing, etc.), or any other relevantparameters. Parameters may be input by a user, for example, via acomputing device, or received from other components of an automatedproduction system.

Although not depicted in FIG. 1, in some embodiments, step 102 mayinclude processing data (e.g., data included in the received inputs) bya computer processing system. For example, step 102 may include imageprocessing to prepare a received digital image for use in defining arelief pattern. As an illustrative example, a digital image including adesign in black against a white background defining a relief pattern maybe processed to invert color values such that the printed portions(i.e., the black portions of the image) define areas of the substratewhich will be protected from removal, for example, by brushing.

Example process 100 continues at step 104 with applying binder ink toform a protective layer over a region of the surface of a substratebased upon the received input. FIG. 2A shows a profile view of asubstrate 200 and FIG. 2B shows a profile view of the same substrate 200with binder ink applied to form a protective layer over a region of thesurface of the substrate 200.

As previously discussed, in some embodiments, the substrate 200 may be aceramic tile. The example substrate 200 depicted in FIGS. 2A-2B ismulti-layered and includes at least a top layer 200 a and a bottom layer200 b. The top layer 200 a may be a double charge layer of a doublecharge vitrified tile. Double charged tiles are typically thicker thanstandard tiles by a few millimeters (mm) making them well suited togenerating relief through subtractive processing. However, a personhaving ordinary skill in the art will recognize that introducedtechnique can similarly be applied to substrates having more or fewerthan two layers. Further, the depth of the top layer 200 a may beexaggerated in FIGS. 2A-2C relative to the depth of the bottom layer 200b for illustrative clarity. In the case of a double charged tile, whichtypically has a total thickness of approximately 5-10 mm, the top layer200 a (or double charge layer) will typically account for approximately10-30% of the total thickness.

As depicted in FIG. 2B, the binder ink can be applied using an inkjetprocess involves propelling droplets 220 of the binder ink into thesurface of the substrate 200. The droplets of binder ink 220 arerepresented by circles that are exaggerated in size relative to thesubstrate. The typical size of the inkjet droplets is on the order ofseveral microns. The droplets 220 of binder ink are applied to thesurface of the substrate 200 via a digital inkjet process to recreate(i.e., print) the digital image (or processed version thereof) receivedas an input at step 102 of example process 100. In other words, adigital inkjet printer prints a digital image on the surface of thesubstrate 200 using binder ink. As a result, the surface of thesubstrate 200 includes regions 222 which are covered in a layer ofbinder ink and unprotected regions 232 which are not covered in a layerof binder ink.

Note that the protected layer covering regions 222 of the substrate 200is depicted as extending into the surface of the substrate 200 (theregions of diagonally hatched lines) as opposed to resting on top of thesurface of the substrate 200. This may be due to absorption of thebinder ink by the porous material of the substrate 200. In otherembodiments involving non-porous or less-porous material, the binder inkmay instead rest on top of the surface of the substrate. In any case,the depth to which the binder ink is absorbed into the surface of thesubstrate will depend on a number of factors including the force of theinkjet process, the amount of ink applied, and the porosity of thesubstrate surface. Further, the depth to which the binder ink isabsorbed may be exaggerated in FIGS. 2B and 2C for illustrative clarityand is not necessarily indicative of actual absorption.

Although not depicted in FIG. 1, in some embodiments example process 100may include waiting for the binder ink to dry or actively applyinganother process, such as a curing process to finalize formation of theprotective layer over certain regions of the surface of the substrate.For example, in some embodiments the binder ink may include or becombined with a curable agent which requires a curing process (e.g.,application of heat, UV light, etc.) to form the protective layer.

Once a protective layer is formed by application of the binder ink,example process 100 proceeds to step 106 which includes removingunprotected regions of the surface of the substrate to form the reliefpattern in the substrate. For example, FIG. 2C shows the removal ofmaterial from the substrate 200 in the unprotected region 232 betweenthe protected regions 222.

In some embodiments, step 106 is performed by brushing away materialfrom the unprotected region 232 of the surface of the substrate.Brushing may be applied manually or preferably automatically using anytype of brushing device. Brushes may comprise fibers (e.g., cotton,polyester, polyamide, polyethylene, polyacrylonitrile, polypropylene,wool, or animal hair) that are affixed to rotatable drums or circularpads. The physical properties of the brushes used in the brushingprocess will depend on several factors such as the type of substrate,the manufacturing process, or decorative requirements. For example, alooser substrate powder, slower production speed, and simple design mayrequire a less aggressive brushing process to achieve a desireddecorative effect. In some embodiments, a brushing process is applied tothe entire surface of the substrate, but the total brushing area mayalso be limited depending on the desired decorative effect.

In some embodiments, the removal of material from the substrate at step106 may be performed using non-contact processes such as compressed air(i.e., air-knife) or powder vacuum. In some embodiments, suchnon-contact processes may be combined with a mechanical brushing toremove material from the surface of the substrate.

As shown in FIG. 2C, removal of material from the unprotected region 232of the substrate 200 results in the formation of a 3D relief of depth Arelative to the original surface of the substrate 200. In the exampledepicted in FIG. 2C, the depth A of the 3D relief is equal to thethickness of the top layer 200 a of the substrate; however, this may notbe the case in all embodiments. For example, in some embodiments, thematerial of the top layer 200 a may exhibit different properties thanthe material of the bottom layer 200 b and the removal process (e.g.,brushing) may be specifically calibrated to only remove the material ofthe top layer 220 a. Alternatively, or in addition, the removal processmay be calibrated (e.g., based on user input received at step 102) toremove material up to a specified depth A that may differ from thethickness of the top layer 200 a. As further depicted in FIG. 2C, the 3Drelief formed by the removal process is defined by vertical side wallsat right angles to the original horizontal surface of the substrate 200.In other words, the 3D relief depicted in FIG. 2C does not exhibit agradient. As will be described later, in some embodiments, the processfor forming the 3D relief can be altered slightly to impart such agradient.

The example process 100 described with respect to FIGS. 2A-2C shows theprotective layer of binder ink remaining in place after the 3D relief isformed. The binder ink may remain in the substrate until it eitherevaporates way or is burned away, for example, during a kiln firingprocess.

Alternatively, in some embodiments this protective layer of binder inkmay be removed from the surface of the substrate after the 3D relief isformed, for example, by applying a solvent. The binder ink may beactively removed through application of a solvent if, for example, thepresence of such binder ink on the surface of the substrate wouldinterfere with other processes such as glazing or color decoration. Insome embodiments, the solvent used to remove the layer of hinder ink maybe the same solvent or similar solvent used to form the gradient relief.

As previously mentioned, in some embodiments one or more post-processesmay be applied after forming the 3D relief according to the introducedtechnique. It shall be understood that such post-processes are optionaland are not required to actually form the relief. FIG. 3 is a flowchartillustrating an example process 300 that can be applied to the substrateafter process 100 has been performed. Certain steps of the exampleprocess 300 are described with reference to FIGS. 4A-4C which show asequence of illustrative diagrams depicting the processing of thesubstrate according to process 300. Certain steps of the example process300 depicted in FIG. 3 may be performed by one or more components of theautomated production system 800 depicted in FIG. 8 and/or the examplecomputing system 900 depicted in FIG. 9. The process 300 described withrespect to FIG. 3 is an example provided for illustrative purposes andis not to be construed as limiting. Other processes may include more orfewer steps than depicted while remaining within the scope of thepresent disclosure. Further, the steps depicted in example process 300may be performed in a different order than is shown.

As mentioned, and as depicted in the flow chart in FIG. 3, process 300picks up after process 100 is completed. In an example embodiment,process 300 begins at step 302 by applying a layer of glaze to thesurface of the substrate 200. As shown in FIG. 4A, in some embodiments,the glaze may be applied by propelling droplets 440 of glaze at thesurface of the substrate 200 to produce a layer 442 of glaze that coversthe surface of the substrate 200 including the 3D relief. Droplets ofglaze may be propelled using any suitable process such as an inkjetprinter similar to the application of the binder ink) or any otherspraying process (automated or manual). The glaze may also be appliedusing any other suitable process such brush application (automated ormanual) or dipping (automated or manual).

In some embodiments, colored ink may be applied at step 304 afterforming the 3D relief in process 100 and/or after applying the glaze atstep 302. Color may be applied for decorative purposes or for any otherpurpose. As shown in FIG. 4B, in some embodiments, the colored ink maybe applied, for example, by propelling droplets 450 of one or morecolors of ink at the surface of the substrate 200 to produce a layer ofcolor 452 on the surface of the substrate or glaze (if applied). Thedroplets 450 of colored ink may be propelled using any suitable processsuch as an inkjet printer (e.g., similar to the application of thebinder ink) or any other spraying process (automated or manual). Thecolored ink may also be applied using any known analog technique such aspaintbrush, gravure, screen printing, etc.

In some embodiments, colored ink is applied using inkjet printing basedon the same digital image used to print the binder ink in process 100.Using digital inkjet printing to both form the 3D relief and applydecorative color allows the formed relief to match (i.e., align with)the digitally printed color designs. This contrasts with the inherentdifficulty in aligning a digitally printed image with a relief formedusing an analog process such as stamping. In some embodiments, thecolors to be applied during step 304 are defined by data in the digitalimage itself and/or by additional input received, for example from auser, at step 102.

Depending on the type of substrate used, example process 300 mayconclude with, at step 306, firing (i.e., applying heat to) thesubstrate to produce the final product 490, for example, as depicted atFIG. 4C. Note that the previously defined layers 200 a and 200 b ofsubstrate 200 have combined through the firing process to produce afinal tile product 490. This biting process may similarly be appliedwithout the application of a glaze or decorative color ink. Aspreviously mentioned, a typical industrial ceramic tile process involvesfiring for approximately 1-2 hours at a temperature between 1030° C. and1250° C.; however, the specifics of the firing process, if applied, willdepend on the material of the substrate.

The introduced technique can further be used to apply gradient 3D reliefto a substrate. FIG. 5 shows a flowchart illustrating a second exampleprocess 500 for applying gradient 3D relief to a substrate using digitalinkjet technology. Certain steps of the example process 500 aredescribed with reference to FIGS. 6A-6D which show a sequence ofillustrative diagrams depicting processing of a substrate according tothe introduced technique. Certain steps of the example process 500depicted in FIG. 5 may be performed by one or more components of theautomated production system 800 depicted in FIG. 8 and/or the examplecomputing system 900 depicted in FIG. 9. The process 500 described withrespect to FIG. 5 is an example provided for illustrative purposes andis not to be construed as limiting. Other processes may include more orfewer steps than depicted while remaining within the scope of thepresent disclosure. Further, the steps depicted in example process 500may be performed in a different order than is shown.

Example process 500 begins at step 502 with receipt of an input definingthe relief pattern that will be applied to a substrate such as a ceramictile. The input received at step 502 may be the same or contain similardata as the input received at step 102 in example process 100 describedwith respect to FIG. 1. In some embodiments, in addition to defining therelief pattern, the input received at step 502 may define the gradientto be applied in the relief pattern. The gradient may be defined forexample, as a separate parameter, for example, input by a user.Alternatively, the gradient may be defined by the digital image includedwithin the input. For example, the digital image may be include gradientvalues (e.g., between black and white) that, when processed by acomputer processing system, can be interpreted as a gradient property ofthe 3D relief to be formed in the substrate.

Example process 500 continues at step 504 with applying binder ink toform a protective barrier layer over a portion of the surface of thesubstrate based upon the input received at step 502. Step 504 ofapplication of binder ink to the surface of a substrate may be the sameor similar to step 104 in example process 100 described with respect toFIG. 1. For example, similar to FIG. 2A. FIG. 6A shows a profile view ofa substrate 600 which includes a top layer 600 a (e.g., a double chargelayer) and a bottom layer 600 b. FIG. 6B shows a profile view of thesame substrate 600 with binder ink applied to form a protective layerover a region of the surface of the substrate 600. As with step 104 inprocess 100, step 504 may include application of the binder ink using aninkjet process by propelling droplets 620 of the binder ink into thesurface of the substrate 600. As a result, the surface of the substrate600 includes regions 622 b that are covered in a layer of binder ink andunprotected regions 632 b that are not covered in a layer of binder ink.

Example process 500 continues at step 506 with the application ofsolvent ink over the applied binder ink to force at least some of theapplied binder ink into the substrate. For example, as depicted in FIG.6C, the solvent ink can be applied using an inkjet process by propellingdroplets 624 of solvent ink into the surface of the substrate.Application of the droplets 624 of solvent ink forces at least some ofthe previously applied binder ink to sink into the substrate 600.

The depth to which the binder ink sinks into the substrate 600 maydepend upon the amount of solvent ink applied at any given area. Varyingthe amount of solvent ink applied across the surface of the substrate600 (e.g., as indicated by the varying number of droplets 624) cantherefore produce a gradient in the protective layer formed by thebinder ink within the substrate 600. This is represented in FIG. 6C bythe protected regions 622 c that are now within the top layer 600 a ofthe substrate 600 and are at an angle relative to the horizontal surfaceof the substrate.

The depth to which the binder ink sinks within the substrate will alsodepend upon the material properties of the substrate. In the exampledepicted in FIG. 6C, the protective layer 622 of binder ink has onlysunk as far as the depth of the top layer 600 a (e.g., the double chargelayer) of the substrate 600. This may be due, for example, to a higherporosity of the top layer 600 a relative to the bottom layer 600 b. Aspreviously discussed, the introduced technique can similarly be appliedin substrates having more or fewer than two layers. Accordingly, inother embodiments, the addition of solvent ink may affect the layer ofbinder ink differently than as depicted in FIG. 6C.

Although not depicted in FIG. 5, in some embodiments, example process500 may include waiting for the binder ink to dry or actively applyinganother process to finalize formation of the protective layer 622 cwithin the substrate 600. For example, in some embodiments, the binderink may include or be combined with a curable agent that requires acuring process (e.g., application of heat, UV light, etc.) to form theprotective layer 622 c. As another example, a washing process may beapplied to remove excess solvent ink from the substrate 600.

Once a protective layer is formed by application of the binder ink andsolvent ink, example process 500 proceeds to step 508 which includesremoving material from unprotected regions (e.g., unprotected region 632c) of the surface of the substrate to form the relief pattern in thesubstrate. For example, FIG. 6D shows the removal of material from thesubstrate 600 in the unprotected region 632 c between the protectedregions 622 c.

As shown in FIG. 6C, removal of material from the unprotected region 632c of the substrate 600 results in the formation of a 3D relief of depthB relative to the original surface of the substrate 600. In the exampledepicted in FIG. 6D, the depth B of the 3D relief is equal to thethickness of the top layer 600 a of the substrate; however, this may notbe the case in all embodiments. For example, in some embodiments, thematerial of the top layer 600 a may exhibit different properties thanthe material of the bottom layer 600 b and the removal process (e.g.,brushing) may be specifically calibrated to only remove the material ofthe top layer 620 a. Alternatively, or in addition, the removal processmay be calibrated (e.g., based on user input received at step 502) toremove material up to a specified depth B that may differ from thethickness of the top layer 600 a. As further depicted in FIG. 6D, the 3Drelief formed by the removal process is defined by sloped side walls. Inother words, the resulting relief has a gradient. More specifically, thegradient of the resulting relief can be defined based on the ratiobetween the elevation change of the sloped side walls (i.e., gradientdepth B) and the horizontal length C of the sloped side walls. Note thatthe resulting side walls in the example depicted in FIG. 6D have aconstant slope. The introduced technique can similarly be applied toform side walls with varying slope, for example, by adjusting how thesolvent ink is applied at step 506.

As previously mentioned, in some embodiments one or more post-processesmay be applied after forming the 3D relief according to the introducedtechnique. Again, FIG. 3 shows a flowchart illustrating an exampleprocess 300 that can be applied to a substrate after forming the reliefFIGS. 7A-7C show a sequence of illustrative diagrams depicting theprocessing of the substrate 600 according to the previously describedprocess 300. Specifically, FIG. 7A shows the application of droplets 740of glaze to the surface of substrate 600 to form a layer 742 of glaze.FIG. 7B shows the application of droplets 750 of colored ink to producea layer of color 752 on the surface of the substrate 600 or glaze (ifapplied). FIG. 7C shows a final product 790 which results from firingthe substrate 600.

Example Implementation of Applying 3D Relief to a Substrate UsingDigital Inkjet Technology

FIG. 8 is a diagram of an example automated production system 800 thatcan be configured to implement the introduced technique for applying 3Drelief to a substrate using digital inkjet technology. The automatedproduction system 800 may be configured, for example, to mass produceceramic tiles with 3D relief using the introduced technique.

The automated production system 800 may include a master controller 802for the automated production system 800 controls one or more controllersfor related subsystems based on received inputs 804. The mastercontroller may include any combination of hardware and/or softwareconfigured to receive the inputs 804, process the inputs 804, andgenerate outputs, for example, in the form of control commands to one ormore subsystems based on the processing.

The inputs 804 received by the master controller may include, forexample, digital image data and/or any other input as described withrespect to steps 102 and 502 of example processes 100 and 500(respectively).

The automated production system 800 may further include an inkjetprinting system configured to apply various types of ink to the surfaceof a substrate 850. The inkjet printing system may include a printsystem controller 806 comprising any combination of hardware and/orsoftware configured to receive control commands from the mastercontroller 802, interpret the commands, and generate control commandsconfigured to cause one or more inkjet printers 807 to propel dropletsof various types of ink onto the surface of the substrate. The varioustypes of ink may include, for example, binder ink, solvent ink, andcolor ink. In some embodiments, the inkjet printing system includesmultiple inkjet printers each configured to apply to a different type ofink.

The automated production system 800 may further include a brushingsystem configured to remove material from the surface of a substrate 850to form 3D relief patterns. The brushing system may include a brushingsystem controller 808 comprising any combination of hardware and/orsoftware configured to receive control commands from the mastercontroller 802, interpret the commands, and generate control commandsconfigured to cause one or more automated brushers 809 to brush thesurface of the substrate 850 to remove material from the surface of thesubstrate. Although not depicted in FIG. 8, other types of mechanicaland/or chemical systems for removal of material from the surface of thesubstrate 850 may similarly be integrated into an automated productionsystem.

The automated production system 800 may further include a glazing systemconfigured to apply a glaze to the surface of the substrate 850 afterthe 3D relief has been formed using the inkjet printing system and thebrushing system. The glazing system may include a glaze controller 810comprising any combination of hardware and/or software configured toreceive control commands from the master controller 802, interpret thecommands, and generate control commands configured to cause one or moreglaze applicators 811 to apply a glaze to the surface of the substrate850. As previously discussed, in some embodiments, glaze maybe appliedthrough inkjet printing, in which case the glazing system may be part ofthe inkjet printing system. Alternatively, the glazing system maycomprise a separate automated system as indicated in FIG. 8.

The automated production system 800 may further include an automatedkiln configured to fire the substrate 850 to produce the final tileproduct. The automated kiln may include a kiln system controller 812comprising any combination of hardware and/or software configured toreceive control commands from the master controller 802, interpret thecommands, and generate control commands configured to cause one or moreheating elements 813 to apply heat to the substrate 850 to produce thefinal tile product.

Various components of the automated production system 800, such as thevarious system controllers 802, 806, 808, 810, and 812 may include oneor more of the components of the example computing system 900 describedwith respect to FIG. 9. It shall be appreciated that the example system800 described with respect to FIG. 8 is an example and is described insimplified terms for illustrative clarity. A person having ordinaryskill will recognize that, in practice, a similar system may includemore or fewer components than are shown or may order and arrange thecomponents differently, while still remaining within the scope of thedisclosed innovation.

Example Computing System

FIG. 9 is a block diagram of an example computing system 900 as may beused to implement certain features of some of the embodiments. Thecomputing system 900 may be a server computer, a client computer, apersonal computer (PC), a user device, a tablet PC, a laptop computer, apersonal digital assistant (PDA), a cellular telephone, a telephone, aweb appliance, a network router, switch or bridge, a console, ahand-held console, a (hand-held) gaming device, a music player, anyportable, mobile, hand-held device, wearable device, or any othermachine capable of executing a set of instructions (sequential orotherwise) that specify actions to be taken by that machine.

The computing system 900 may include one or more processing units (e.g.,central processing units (CPU) and/or graphical processing units (GPU)(collectively the “processor”) 905, one or more memory units(collectively “memory”) 910, one or more input/output devices 925 (e.g.keyboard and pointing devices, touch devices, display devices, audioinput/output devices, etc.) one or more storage devices 920 (e.g. diskdrives, solid state drives, etc.), and one or more network adapters 930(e.g., network interfaces) that can communicatively couple via aninterconnect 915. The interconnect 915 is illustrated as an abstractionthat represents any one or more separate physical buses, point to pointconnections, or both connected by appropriate bridges, adapters, orcontrollers. The interconnect 915, therefore, may include, for example,a system bus, a Peripheral Component Interconnect (PCI) bus orPCI-Express bus, a HyperTransport or industry standard architecture(ISA) bus, a small computer system interface (SCSI) bus, a universalserial bus (USB), IIC (12C) bus, an Institute of Electrical andElectronics Engineers (IEEE) standard 1394 bus (also called Firewire),or any other suitable system for facilitating communication between thevarious components of the example computing system 900.

The memory 910 and storage device 920 are computer-readable storagemedia that may store instructions that implement at least portions ofthe various embodiments. In addition, the data structures and messagestructures may be stored or transmitted via a data transmission medium(e.g., a signal on a communications link). Various communication linksmay be used such as the Internet, a local area network, a wide areanetwork, or a point-to-point dial-up connection, etc. Thus, computerreadable media can include computer-readable storage media, e.g.non-transitory media, and computer-readable transmission media.

The instructions stored in memory 910 can be implemented as softwareand/or firmware to program the processor 905 to carry out actionsdescribed above. In some embodiments such software or firmware may beinitially provided to the processor 905 by downloading the software orfirmware from a remote system through the computing system 1500, e.g.,via network adapter 930.

The various embodiments introduced herein can be implemented by, forexample, programmable circuitry, e.g., one or more microprocessors,programmed with software and/or firmware, or entirely in special-purposehardwired (non-programmable) circuitry, or in a combination of suchforms. Special-purpose hardwired circuitry may be in the form of, forexample, one or more ASICs, PLDs, FPGAs, etc.

What is claimed is:
 1. A method for forming a three-dimensional (3D)relief in a substrate, the method comprising: receiving an inputdefining a relief pattern; applying binder ink to a first region of asurface of the substrate based on the received input, the applied binderink forming a protective barrier over the first region of the surface ofthe substrate; and removing material from an unprotected second regionof the surface of the substrate to form the 3D relief in the substratebased on the relief pattern.
 2. The method of claim 1,herein the inputncludes a digital image of the relief pattern.
 3. The method of claim 1,wherein the binder ink is applied using a digital inkjet process basedon the input.
 4. The method of claim 1, wherein the input includes adigital image of the relief pattern and wherein applying the binder inkincludes: processing the received digital image to determine the firstregion of the surface of the substrate; and propelling droplets of thebinder ink at the first region of the surface of the substrate torecreate the relief pattern.
 5. The method of claim 1, wherein removingthe material from the unprotected second region of the surface of thesubstrate includes: brushing the surface of the substrate, whereinbrushing the surface of the substrate removes material from theunprotected second region of the surface of the substrate, but does notremote material from the first region of the surface of the substratedue to the protective barrier formed by the binder ink.
 6. The method ofclaim 1, wherein the binder ink includes a resin solution.
 7. The methodof claim 1, wherein the substrate includes a top layer of absorbentmaterial upon which ink can be applied using digital inkjet printing. 8.The method of claim 1, wherein the substrate is a double charged ceramictile.
 9. The method of claim 1, further comprising: applying solvent inkto the surface of the substrate after applying the binder ink to thefirst region of the surface of the substrate and before removing thematerial from the unprotected second region of the surface of thesubstrate; wherein applying the solvent ink causes at least some of thebinder ink to sink into the surface of the substrate such that theprotective layer formed by the binder ink is at a gradient depthrelative to the surface of the substrate; and wherein removing thematerial from the unprotected second region of the surface of thesubstrate forms a gradient 3D relief.
 10. The method of claim 1, furthercomprising: applying a glaze to the surface of the substrate afterforming the 3D relief.
 11. The method of claim 1, further comprising:applying color ink to the surface of the substrate after forming the 3Drelief
 12. The method of claim 1, further comprising: firing thesubstrate after forming the 3D relief to produce a ceramic tile.
 13. Asystem for forming a three-dimensional (3D) relief in a substrate, thesystem comprising: a digital inkjet printer configured to: receive adigital image of a relief pattern; and apply, based on the receiveddigital image, binder ink to a first region of a surface of thesubstrate to form a protective barrier over the first region of thesurface of the substrate: and a mechanical brusher configured to: brushthe surface of the substrate to remove material from an unprotectedsecond region of the surface of the substrate to form the 3D relief inthe substrate based on the relief pattern.
 14. The system of claim 13,wherein the input includes a digital image of the relief pattern andwherein the digital inkjet printer is configured to apply the binder inkby: processing the received digital image to determine the first regionof the surface of the substrate; and propelling droplets of the binderink at the first region of the surface of the substrate to recreate therelief pattern.
 15. The system of claim 13, wherein the binder inkincludes a resin solution.
 16. The system of claim 13, wherein thesubstrate is a double charged ceramic tile including a top layer ofabsorbent material upon which ink can be applied using digital inkjetprinting.
 17. The system of claim 13, wherein the digital inkjet printeris further configured to: apply solvent ink to the surface of thesubstrate after applying the binder ink to the first region of thesurface of the substrate and before the mechanical brusher has removedthe material from the unprotected second region of the surface of thesubstrate; wherein applying the solvent ink causes at least some of thebinder ink to sink into the surface of the substrate such that theprotective layer formed by the binder ink is at a gradient depthrelative to the surface of the substrate; and wherein removing thematerial, by the mechanical brusher, from the unprotected second regionof the surface of the substrate forms a gradient 3D relief.
 18. Thesystem of claim 13, further comprising: a glazing apparatus configuredto apply a glaze to the surface of the substrate after the 3D relief hasbeen formed.
 19. The system of claim 13, wherein the digital inkjetprinter is further configured to: apply color ink to the surface of thesubstrate after the 3D relief has been formed.
 20. The system of claim13, further comprising: an automated kiln configured to fire thesubstrate after the 3D relief has been formed to produce a ceramic tile.21. A system for forming a three-dimensional (3D) relief in a substrate,the system comprising: a processor; and a memory coupled to theprocessor, the memory including instructions stored thereon, executableby the processor, to cause the system to: receive an input defining arelief pattern; process the received input to generate a first set ofcontrol commands configured to cause an inkjet printer to: apply binderink to a first region of a surface of the substrate based on thereceived input, the applied binder ink forming a protective barrier overthe first region of the surface of the substrate; and process thereceived input to generate a second set of control commands configuredto cause a mechanical brusher to: brush the surface of the substrate toremove material from an unprotected second region of the surface of thesubstrate to form the 3D relief in the substrate based on the reliefpattern.
 22. The system of claim 21, wherein the binder ink includes aresin solution.
 23. The system of claim 21, wherein the substrate is adouble charged ceramic tile including a top layer of absorbent materialupon which ink can be applied using digital inkjet printing.
 24. Thesystem of claim 21, where the memory has further instructions storedthereon, executable by the processor, to cause the system to further:generate a third set of control commands configured to cause the inkjetprinter to apply solvent ink to the surface of the substrate afterapplying the binder ink to the first region of the surface of thesubstrate and before the mechanical brusher has removed the materialfrom the unprotected second region of the surface of the substrate;wherein applying the solvent ink causes at least some of the binder inkto sink into the surface of the substrate such that the protective layerformed by the binder ink is at a gradient depth relative to the surfaceof the substrate; and wherein removing, by the mechanical brusher, thematerial from the unprotected second region of the surface of thesubstrate forms a gradient 3D relief.
 25. The system of claim 21, wherethe memory has further instructions stored thereon, executable by theprocessor, to cause the system to further: generate a fourth set ofcontrol commands configured to cause a glazing apparatus to apply glazeto the surface of the substrate after the 3D relief has been formed. 26.The system of claim 21, where the memory has further instructions storedthereon, executable by the processor, to cause the system to further:generate a fifth set of control commands configured to cause the inkjetprinter o apply color ink to the surface of the substrate after the 3Drelief has been formed.
 27. The system of claim 21, where the memory hasfurther instructions stored thereon, executable by the processor, tocause the system to further: generate a sixth set of control commandsconfigured to cause an automated kiln to fire the substrate after the 3Drelief has been formed to produce a ceramic tile.